Piano mechanism



Nov. 30; 1948. A. N. PREVOST 2,455,139

PIANO MECHANISM Filed July 18. 1946 2 Sheets-Sheet 1 Nov. 30, 1948. A.N. PREVOST 2,455,139

PIANQ MECHANISM Filed July 18. 1946 2 Sheets-Sheet 2 Patented Nov. 30,1948 UNITED STATES PATENT OFFICE."

PIANO MECHANISM Auxance N. Prevost, Deep River, Conn.

Application July" 18, 1946, Serial No. 684,432 r 18 Claims (01. 8 4-240)The present invention relates to p anos, and more particularly to animproved combination of key, key frame and action particularly adaptedfor use in upright pianos.

It is an object of the invention to provide an efficient and compactaction especially designed to make smaller upright pianos which may belower in height above the keyboard and with a minimum of distance fromthe front of the keys to the piano strings.

It is an advantage of the present invention that the use of manyconventional parts of piano actions may be eliminated without acorresponding loss of function, whereby the invention may beeconomically and more easily constructed.

It is a further advantage of the invention that the keys, key frame andaction may be constructed as a complete unit which may be easilyassembled with the usual piano frame and strings.

A further advantage of the invention is the ease with which the parts ofthe action may be adjusted after assembly of the device.

The accomplishment of the foregoing advantages as well as others will bereadily apparent from the following description of a specific embodimentof the invention shown in the accompanying drawings, in which Figure lis a side view partly in cross section showing the completely assembleddevice in rest position;

Fig. 2 is a view similar to Fig. 1 showing the device after rebound ofthe hammer away from the string;

Fig. 3 is a similar view of the device at the instant when the hammerstrikes the string; and

Fig. 4 is aside view partly in cross section showing the manner ofinterconnecting the supporting members of the assembly.

Referring to Figs. 1 to 3 of the drawings, a piano key I is shownpivotally mounted at 2 on a key frame 3. Unlike keys of conventionalpiano assemblies, the key I is adapted to function as an integral partof the piano action. As will be explained more fully hereinafter, it isthis additional functioning of the keys which largely contributes to theaccomplishment of the foregoing objects and advantages.

The rear end of the key I is provided with a shoulder 8 disposed at apredetermined angle and is preferably covered with a felt cushion 9. Thefunction of the cushioned shoulder 8 on the key I as part of the actionwill be explained more fully hereinafter.

To permit adjustment of the key in respect to its functioning as part ofthe action, there is pro- 2 I vided an elongated memberA-mounted forlimited pivotal movement at one end to the key by a screw 5.Displacement of the member 4 away from the key I is caused by arelatively strong biasing spring member 6. However, the angular positionof the member 4 with respect to the key I is determined by an adjustableset screw 7.

The adjustable elongated member 4 is provided with a shoulder orabutment I0 having a flange 26 at its free end which preferably iscovered with a deerskin pad I I. Immediately forward of the abutment I0there is a felt covered recess I2. The shoulder I0 and felt coveredrecess I2 function as bearing surfaces in the operation of the key aspart of the action, as will be explained more fully hereinafter. 1 I IMounted on the member 4 and adapted to be adjustably positionedtherewith is a felt pad I3 mounted on a supporting member I I. The feltpad I3 isprovided with two spaced openings I5 and I6 which may beslotted at one side for convenience in assembling the device, theseopenings being adapted to receive connecting wires I7 and I8 which areconnected [tQOtheI parts of the action, as described hereinafter. :Alsomounted on the member 4 is an upright member 3I also functioning as partof the action. I I

The remainder of the piano action is mounted on a conventional actionrail I9. In the specific embodiment shown, the remaining parts of theaction are positioned on a single mounting bracket or hanger 20'se'curedto the top of theaction rail I9. The use of a single mounting bracketgreatly facilitates the aligningof'the cooperating parts upon assemblyof the device.

On one side of the mounting bracket or hanger 29 there is pivoted thebutt'ZI of a conventional felt covered hammer 22. The butt2I may beprovided with an extension 36 adjacent the hammer 22 for resting upon aconventional cushioned hammer rest rail 21. The lower end of the butt 2|comprises an extension 25 below the pivot-point disposed at a slightpredetermined angle to the butt where it can cooperate with the shoulder8 on key I as described hereinafter. A spring member 39 connects thebutt 2| to the upright member 3| previously described.

Pivoted to the butt 2| approximately midway between the hammer 22 andthe mounting bracket 20 is a fly 23 so designed that its lower endreaches the shoulder I0 when the device is at rest.

The lower end of the fly 23 is secured to the connecting wire Ill-which,as described'above, is received through the felt pad I3. Adjustable stopnuts 24 and 38 are threaded on the end of the connecting wire l8 and aredisposed on either side of the felt pad It: for the purpose describedbelow.

The operation of these components of the device hereinbefore describedwill be more readily understood from the following description of theoperation when the piano key I is struck and then released. As shown inFig. 1, the lily 23 is resting upon the shoulder tll when the device isat rest. This position is insured by the adjustable nut 38 on theconnecting wire 18 which abuts against the felt pad l3. When the key Iis struck, the upward movement of the rear portion :of the key causesthe shoulder ID to push upwardly on the fly 23 thereby actuating thehammer 22. When the movement has progressed to an extent short of fulldepression of the key, the fold .pad I3 is pivoted against theadjustable stop 'nut "2'4 on the connecting wire l8, thereby pulling the'fiy '23 off of 'the shoulder 1 0. The inertia of the hammer 22,however, is su'fiicient to cause the hammer to continue on and strikethe strin denoted by the dot and dash line 3i. The hammer 22 thenreboundsto'the position shown in Fig. 2 "aided by the spring member 39which also effectively prevents repeat of the hammer against the string,by which time the key has been fully depressed so that the extension 25"on the butt 21 meets-the cushioned shoulder 8 of the key I. At 5 thesame time, the end of the fly 2% rests on the felt covered recess 1 2 ofthe pivoted member 4 "on the key "I. This provides a three-corneredsupport for "the hammer 2'2 and eliminates the need'fortheconventional'backc'heck usually provided in piano actions. Thetriangulation of the key I, butt 2 and fly 23 also provides an upper"limit for movement'of the key I which eliminates the need for a :pad'on the key framebeneath the forward-end 0f the keys to limit theirmovement.

Upon :release of the key l, the parts return to the position shown in.Fig. 1 with the fly 23 being moved ?to"its rest position on theshoulder 10 by reason of the a'dtiustable'nut 38 on the con-- nectingwire ill-which, in this position, comes in 1 contact with the feltpad 13 as described above. The hammer rest rail 2"! may 'beoperativelyposition'ed "with the device in any conventional -man- =ner. The springmember '39 helps to bring the hammer back to the rest position againstthe hammerrest rail -21.

The remaining parts of the device, whose relationship to the partsdescribed above will be readily apparent, comprise a damper '28 pivotedon the bracket or hanger which is secured to the top of the action rail19. The damper 28 is connected at an intermediate point to theconnedting wire 11 which, as discussed above, is received through'an'opening it in the felt pad l3. Adjustable stop'nuts 2-9 and 4!] areprovided on the end of the connection wire I! and are disposed on*e'ither -s'ide of "the felt pad 13. A spring "member is connected atoneend to the adjust- 'able'stop nut and at the other end to 'an uprightmember 42 positioned on the action rail 19. The hammer butt 2| and fly2-3 may be formed with an offset portion to permit the wire "and springmember 41 to pass by withoutbinding movement of the felt pad IS, thefelt .pad acts againstthe adjustable nut '29 toapply at'ens'ionunitaryassembly is shown.

ings.

ing pull on the connecting wire l! which moves the damper 28 away fromthe piano wire 31 before the hammer 22 strikes the wire, as shown inFig. 3. Adjustable stop nut lll limits move ment of the damper so thatit will not interfere with the action of the hammer 22. Upon release ofthe key I, the damper 28 is returned to a position against the pianostring by reason of the spring member 4| acting upon the connecting wire11 through its connection with the adjustable stop nut 40. At the sametime, the adjustable stop nut 29 contacts the felt member l3 therebybiasing the key into its normal at rest position as shown in Fig. 1. Inthis construction it will be noted that the use of the conventionalspoon and wippen has been eliminated.

Referring to Fig. 4, the interconnecting of the key frame 3 and actionrail it to form a single For this purpose, there is provided a pluralityof brackets 32 which are adapted to be secured at each end of the keyframe 3 and two of which are adapted to be secured intermediate the endsin the breaks between the keys. Each bracket may be formed with a fixedextension 33 and pivoted extension 34 adapted to fit around the top andbottom of the action rail l9 and to be securely connected thereto bymeans of a bolt 35.

If desired, the complete action and keyboard assembly can be constructedas a single unit for ready insertion into a piano frame, or, if desired,th'epiano key frame and the keys with their associated parts of thepiano action may be provided as one unit and the action rail (9 andassociated action parts may be provided as a second assembly, all ofwhich may be readily assembled in the place of use by means of thebrackets 32.

The ease with which the assembly may be adjusted will be readilyapparent from the draw- In the embodiment shown, the adjustable stopnuts "24, 3.8, 40 and 29 are disposed toward the .front of the devicewhere they are readily accessible. With the action in rest position, theset screw 1 is adjusted until the lower end of fly 23 comes in contactwith the shoulder I0. Then the stop nut 29 is adjusted so that it restslightly against the felt pad l3 to insure that the key will be returnedto rest position. The stop nut 38 may then be adjusted to insure thatthe fl y 23 will be effectively positioned on the shoulder [0. The keyisthen lightly but fully depressed and the adjustable nut 40 is turned toset the desiredmaximum clearance of the damper 28 from the piano string.The next adjustment is by means of the adjusting nut 24 which is turnedto a point where the lower end of the .fly 23 is pulled from theshoulder or abutment ill so that the hammer is free to rebound from thestring.

As described above, a particular advantage of 'the'device *of thepresent invention lies in the :use "of the piano key as apart of thepiano action 'nected key frame and action rail with all parts of theaction supported thereon, the assembly and disassembly of the device hasbeen materially improved. Among the decided advantages of such aninterconnection is the ease with which all the parts are aligned and theelimination of extra supports and adjustments generally provided in thepiano cabinet.

In light of the above description of a specific embodiment of theinvention, it will be apparent that one skilled in the art will be ableto make modifications and improvements within the scope of thisinvention, and all such modifications and improvements are intended tobe included within the scope of the following claims.

I claim as my invention:

1. In a piano, the combination comprising a key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame, andan action consisting solely of members mounted on the action rail andmembers mounted on the key, said members on the key being adapted toactuate and control the members mounted on the action rail upon pivotingmovement of the key, said first and second named members beingconstructed and arranged to return said key to original position uponrelease of the key.

2. In a piano having a key frame and a plurality of keys pivotallymounted on the key frame, an action rail, an action comprising a hammerhaving a butt pivotally supported on the action rail, a downwardlyextending fly pivotally connected to the hammer butt and means on thekey for en gaging the end of the fly to actuate the hammer upon pivotingmovement of the key, and means for removably supporting the action railon the key frame whereby the action rail and action members supportedthereon may be removed as a unit independently of the key framecomprising a plurality of separate brackets attached at one end to theaction rail and adapted to rest at the other end at spaced intervals onthe key frame so as to be removable therefrom without removing the keys.

3. In a piano, the combination comprising a key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame, andan action comprising a spring biased hammer having a butt pivotallysupported on the action rail, a downwardly extending fly pivotallyconnected to the butt, means on the rear portion of the key foractuating the hammer through engagement with said fly, and meansresponsive to position of the key for engaging and disengaging the flyfrom the first-named means.

4. In a piano, the combination comprising a key frame, a spring biasedkey pivotally mounted on the key frame, an action rail connected to thekey frame, and an action comprising a hammer having a butt pivotallysupported on the action rail, a downwardly extending fly pivotallyconnected to the hammer butt, means on the rear end of the key adaptedto engage the fly when the key is depressed thereby actuating thehammer, and means comprising an element mounted on said key forpositioning the fly on said firstnamed means when the combination is atrest and for disengaging the fly from said means when the key is partlydepressed.

5. In a piano, the combination comprising a key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame, andan action comprising a hammer, a butt on said hammer pivotally supportedon the action rail, a fly pivotally suspended from the hammer butt, ashoulder at the rear end of the key for engaging the fly to actuate thehammer, an upright member on the rear end of the key, and means actuatedby the upright member for moving the fiy off the said shoulder when thekey is I ll partly depressed and for returning the fly onto the shoulderwhen the key is released.

6. In a piano, the combination comprising a key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame, aspring biased hammer having a butt pivotally supported on the actionrail, a fly pivotally connected to the hammer butt, a shoulder on therear end of the key for engaging the fly to actuate the hammer when thefront end of the key is depressed, an upright member on the rear end ofthe key having an opening therethrough, a rod connected to the fly andextending through the opening in the upright member, adjustable stopmeans at the end of the rod adapted to be engaged by one side of theupright member when the front end of the key is partially depressedthereby moving the fly off the shoulder, and adjustable stop meansintermediate the ends of I the rod for engaging the other side of theupright member when the key is released thereby returning the fly ontothe said shoulder.

7. In a piano, the combination comprising a key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame,

a hammer having a butt pivotally supported on the action rail, a flypivotally connected to the hammer butt, an elongated member pivoted onthe rear end of the key, means for adjustably positioning said member, ashoulder on the member for engaging the fly to actuate the hammer whenthe front end of the key is depressed, a spring member interconnectingsaid hammer butt and said elongated member for biasing the hammer, anupright member mounted on the elongated member having an openingtherethrough, a rod connected to the fly and extending through theopening 'in the upright member, adjustable stop means at the end of therod adapted to be engaged by one side of the upright member when thefront end of the key is partially depressed thereby moving the fly offthe shoulder, and a stop intermediate the ends of the rod for engagingthe other side of the up right member when the key is released therebyreturning the fly onto the said shoulder.

3. In a piano, the combination comprising key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame, aspring biased hammer having a butt, means for pivotally supporting thehammer on the action rail with the lower portion of the butt ex tendingbelow the supporting means, a fly pivotally connected to the hammerbutt, and a shoulder on the rear portion of the key for actuating thehammer through said fly when the front end of the key is depressed, saidkey being formed with spaced surfaces for engaging the lower portion ofthe hammer butt and the fly respectively to position the hammer when thefront end of the key is fully depressed.

9. In a piano, the combination comprising a key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame, ahammer having a butt, means for pivotally supporting the hammer on theaction rail with a lower portion of the butt extending below thesupporting means, a fly pivotally connected to the hammer butt, ashoulder on the rear por" tion of the key for actuating the hammerthrough engagement with the fly when the front end of the key isdepressed, said key having a supporting surface on the rear end thereofadjacent the said shoulder for receiving the end of the fly when thefront end of the key is fully depressed and having a second shoulder onthe rear end thereof ,for engaging the-lowerportion oi thehammershank-when the front end of the key is'fully depressed, and meansactuated by movement of said key for positioning the fly on the said.supporting surface of the key when the front end of the key is fullydepressed andfor positioning the fly on the first-named shoulder of thekey when the key is fully released.

10. In a piano, the combination comprising a key frame, a key pivotallymounted on the key frame, an action rail connected to the key frame, ahammer having a butt, means for pivotally supportingthe hammer on theaction rail with a lower portion of the butt extending below thesupporting means, a fly pivotally connected to the hammer butt, ashoulder on the rear portion of the key for actuating the hammer throughengagement withthe fly when the front end of the .key is depressed, saidkey having a support ing surface on. the rear end thereof adjacent thesaid shoulder for receiving the end of the fly when the front end of thekey is fully depressed and having a second shoulder on the rear'endthereof for engaging the lower portion of the hammer butt when the frontend of the key is fully depressed, an upright member on the rear end ofthe :key, and means actuated by said upright member upon pivoting of thekey for positioning the fly on the .said supporting surface when thefront end of the key is fully depressed and for positioning the fly'onthe first-named shoulder of the key when'the key is fully released.

11. In a piano, the'combination comprising an action rail, a hammerpivotally supported on the action rail, a damper'pivotally supported onthe action rail, a key'frame, aikey pviotally, mounted on the key frame,a iiy'pivotally connected to the hammer, meanson the rear end of the keyfor engaging the fly to actuate the hammer upon depression of the frontend of the key, and means on the rear end-of the key and connected tothe fly and damper for pivoting the fly and damper when'the front of thekey is partially depressed.

12. In a piano, the combination comprising an action rail, a hammer"pivotally supported on the action rail, a springbiased damper pivotallysupported on the action rail, a key frame, a key pivotally-mounted onthe 'key frame, a fly pivotally connected-to the hammer, a shoulder onthe rear end of the key adapted to actuate the hammer through engagementwith the fly when the front end of the key is depressed, an uprightmember on therear end. of the key, means interconnecting said damper andupright member for actuating said damper when the key is partiallydepressed and for returning the key to original position when released,and means'interconnect ingthe fly and said upright member for moving thefly on the shoulder when'the key is partially depressed and for movingthe fly onto the shoulder when the key is released.

13. In a pianoythe combination comprising an action rail, a hammerhaving a butt pivotally supported on the action rail, a biased damperpivotally supported on the action. rail in substantial alignment withthe hammer, a key frame, a key pivotally supported on the key frame insubstantial alignment with the hammer and damper. a fly extendingbetween the hammer and key for actuating the hammer when the key isstruck, a member pivotedwith the key, connecting means extending betweensaid member and the damper for actuating the damper when the key isdepressed and connecting means-extending between said memberand: thefiyfor-controlling theopported on the action rail, a damper pivotallysupportedon the action rail, a spring'member for biasing said damper, akey frame, a key pivotally supported on the key frame, a shoulder on thekey, a fiy extending between the hammer and said shoulder for actuatingthe hammer when thekey is pivoted,'and means interconnecting the damperand key for actuating the damper when the key is pivoted and forreturning the key to original position when released, said key beingformed with spaced surfaces for engaging the hammer butt and the fly,respectively, to support the hammer ina partially pivoted position whenthe front end of the key is fully depressed.

15. In a piano, the combination comprisingian actionrail, a hammerhaving a butt, means for pivoting the hammer on the action rail with aportion of the hammer butt extending downwardly therefrom, .a springbiased damper pivotally supported on the action rail, a key frameconnected to the'action rai1,-a key pivotally mounted on thekey frame, ashoulder on the key, a fly pivotally mounted on the hammer butt, meansinterconnecting the damper and key to 'limitedly actuate the damper'whenthe key is'pivoted and to return the key to original position whenreleased, and'means extendingbetween the key and the fly for positioningthe fly on the shoulder when the key is at rest whereby the fly will beactuated by said shoulder when the key is pivoted,

F said means being effective for removing the fly from the shoulder whenthe key is partiallypiv oted, saidkey being formed with separatesurfaces for engaging the fly and the said downwardly extending portionof the hammer butt respectively, for supporting the hammer in apartially pivotedposition when the front end of the key isfullydepressed.

16. In a piano, the combination comprisingan action rail, a hammerhaving'a butt, means for pivoting the hammer on the, action rail with aportion of the hammer butt extending downwardly therefrom, a springmember for biasing the hammer, a spring biased damper pivotallysupported on the action rail in substantialalignment with the hammer, akey frame connected to the action rail, a key pivotally mounted on thekey frame in substantial alignment with the damper and hammer, a flypivotally mounted on the hammer butt, an adjustable supporting member onthe rear end of the key, .a shoulder on said member adapted to engagethe fiy to actuate the hammer when the key is pivoted, an upright membermounted on the supporting member, means interconnecting said uprightmember and the damper for limitedly pivoting the damper when the key ispivoted and for returning the key to normal position when released,means interconnecting the fly and said upright member for positioningthe fly on. the shoulder during partial pivoting of the key and on aportion of the supporting member adjacent the shoulder when the key isfully depressed, and a shoulder on the rear portion of the key forengaging downwardly extending portion of the hammer butt when the key isfully depressed whereby the hammer may be supported in partially pivotedposition.

-1'7. 'In-a piano, the combination comprising an action rail, a hammer,a butt on said hammer, a spring biased damper, means' for pivotallysupporting said damper and hammer butt on the action rail, said hammerbutt having a portion extending below said pivot means, a fly pivotallyconnected to the hammer butt, a key frame, a key pivotally mounted onthe key frame, a shoulder on the rear end of the key adapted to engagethe fly for actuating the hammer when the front end of the key isdepressed, an upright member mounted on the rear end of the key,adjustable means engaged by said upright member for limitedly pivotingthe damper when the front end of the key is depressed, and adjustablemeans interconnecting the fly and the upright member for pivoting thefly oil the shoulder when the key is partially depressed and forpositioning the fly on the shoulder when the key is released, said keybeing formed with separate surfaces for engaging the fly and the hammerbutt, respectively to support the hammer in a partially pivoted positionwhen the front end of the key is fully depressed.

18. In a piano, the combination comprising an action rail, a hammer, abutt on said hammer, a damper, means for pivotally supporting saiddamper and hammer butt on the action rail with the hammer and damper inalignment, said hammer butt having a portion extending below said pivotmeans, a fly pivotally connected to the hammer butt, a key frame, a keypivotally mounted on the key frame, means for connecting the action railto the key frame with the key in alignment with the hammer and damper,an elongated member pivoted on the rear end of the key, adjustable meansfor determining the pivoted position of the elongated member on the key,a shoulder on the elongated member spaced from the pivoted end adaptedto engage the fly, an upright member mounted on the elongated memberhaving a plurality of openings therein, a rod connected to said flyslidably received through one of the openings in the upright member,adjustable means on the end of said rod for engaging one side of theupright member when the key is partly depressed thereby pivoting the flyoff the shoulder on the elongated member, a second adjustable means onsaid rod for engaging the other side of the upright member when the keyis released, thereby pivoting the fly onto the shoulder on the elongatedmember, a spring member connected between the hammer butt and theelongated member for biasing the hammer, a rod connected to the damperand slidably received through the other of the openings in the uprightmember, adjustable means on the end of said rod for engaging the uprightmember to actuate the damper when the key is depressed, a secondadjustablemeans on said rod for engaging the other side of the uprightmember to limit pivoting movement of the hammer, a spring memberconnected to said second adjustable means and to the action rail forbiasing the damper and for returning the key to original position whenreleased, a supporting surface on the elongated member adjacent theshoulder, and a shoulder on the rear end of the key, said supportingsurface and said last-named shoulder being adapted to engage the fly andthe portion of the hammer butt extending below the pivoting means,respectively, when the front of the key is fully depressed therebyholding the hammer in a partially pivoted position.

AUXANCE N. PREVOST.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

